Final answer:
In a Western blot, proteins are identified by mixing them with labeled antibodies. Primary antibodies bind to specific proteins, and secondary antibodies with molecular markers facilitate the visualization of these proteins.
Step-by-step explanation:
In a Western blot, a mixture of proteins to be identified is mixed with antibodies that have been labeled.
The Western blot, also known as an immunoblot assay, is a technique used to detect specific proteins in a sample. After separating the proteins by gel electrophoresis, the proteins are transferred to a nitrocellulose membrane. Here, they are probed with a primary antibody that specifically binds to the protein of interest. Following this, a secondary antibody, which is labeled with a molecular marker like an enzyme or a fluorophore, is applied. This allows for the visual detection of the protein, either by fluorescence or by the reaction of the enzyme with a chromogenic substrate that develops color.
The function of the enzyme in Western blotting is to produce a detectable signal that indicates the presence of the target protein. In the case of enzyme-labeled antibodies, the substrate reacts with the enzyme to produce a colored product or emits light, allowing for the visualization of protein bands corresponding to the protein of interest.